Grain-Boundary-Induced Alignment of Block Copolymer Thin Films
Open Access
- 3 January 2020
- journal article
- research article
- Published by MDPI AG in Nanomaterials
- Vol. 10 (1), 103
- https://doi.org/10.3390/nano10010103
Abstract
We present and discuss the capability of grain boundaries to induce order in block copolymer thin films between horizontally and vertically assembled block copolymer grains. The system we use as a proof of principle is a thermally annealed 23.4 nm full-pitch lamellar Polystyrene-block-polymethylmetacrylate (PS-b-PMMA) di-block copolymer. In this paper, grain-boundary-induced alignment is achieved by the mechanical removal of the neutral brush layer via atomic force microscopy (AFM). The concept is also confirmed by a mask-less e-beam direct writing process. An elongated grain of vertically aligned lamellae is trapped between two grains of horizontally aligned lamellae. This configuration leads to the formation of 90° twist grain boundaries. The features maintain their orientation on a characteristic length scale, which is described by the material’s correlation length ξ. As a result of an energy minimization process, the block copolymer domains in the vertically aligned grain orient perpendicularly to the grain boundary. The energy-minimizing feature is the grain boundary itself. The width of the manipulated area (e.g., the horizontally aligned grain) does not represent a critical process parameter.Funding Information
- Horizon 2020 Framework Programme (654360)
This publication has 58 references indexed in Scilit:
- Effect of wall potential on morphology of symmetric diblock copolymers in nanotrenchJapanese Journal of Applied Physics, 2016
- ITRS lithography roadmap: 2015 challengesAdvanced Optical Technologies, 2015
- Defects in the Self-Assembly of Block Copolymers and Their Relevance for Directed Self-AssemblyAnnual Review of Chemical and Biomolecular Engineering, 2015
- A General Design Strategy for Block Copolymer Directed Self-Assembly Patterning of Integrated Circuits Contact Holes using an Alphabet ApproachNano Letters, 2015
- Self-assembling morphologies of symmetrical PS-b-PMMA in different sized confining groovesRSC Advances, 2014
- Integration of nanoimprint lithography with block copolymer directed self-assembly for fabrication of a sub-20 nm template for bit-patterned mediaNanotechnology, 2014
- Two-Dimensional Pattern Formation Using Graphoepitaxy of PS-b-PMMA Block Copolymers for Advanced FinFET Device and Circuit FabricationACS Nano, 2014
- Directed self-assembly of block copolymers for use in bit patterned media fabricationJournal of Physics D: Applied Physics, 2013
- Rectangular Patterns Using Block Copolymer Directed Assembly for High Bit Aspect Ratio Patterned MediaACS Nano, 2010
- Block Copolymers—Designer Soft MaterialsPhysics Today, 1999